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Vector-valued sequence space B M C ( X ) and its properties

Qing-Ying Bu (1996)

Commentationes Mathematicae Universitatis Carolinae

In this paper, a vector topology is introduced in the vector-valued sequence space BMC ( X ) and convergence of sequences and sequentially compact sets in BMC ( X ) are characterized.

Vector-valued wavelets and the Hardy space H¹(ℝⁿ,X)

Tuomas Hytönen (2006)

Studia Mathematica

We prove an analogue of Y. Meyer's wavelet characterization of the Hardy space H¹(ℝⁿ) for the space H¹(ℝⁿ,X) of X-valued functions. Here X is a Banach space with the UMD property. The proof uses results of T. Figiel on generalized Calderón-Zygmund operators on Bochner spaces and some new local estimates.

Weak orthogonality and weak property ( β ) in some Banach sequence spaces

Yunan Cui, Henryk Hudzik, Ryszard Płuciennik (1999)

Czechoslovak Mathematical Journal

It is proved that a Köthe sequence space is weakly orthogonal if and only if it is order continuous. Criteria for weak property ( β ) in Orlicz sequence spaces in the case of the Luxemburg norm as well as the Orlicz norm are given.

Weak uniform continuity and weak sequential continuity of continuous n-linear mappings between Banach spaces.

Rajappa K. Asthagiri (1991)

Extracta Mathematicae

In this paper it is shown that the class LnWU (E1,E2,...,En;F) of weakly uniformly continuous n-linear mappings from E1x E2x...x En to F on bounded sets coincides with the class LnWSC (E1,E2,...,En;F) of weakly sequentially continuous n-linear mappings if and only if for every Banach space F, each Banach space Ei for i = 1,2,...,n does not contain a copy of l1.

Weakly continuous functions of Baire class 1.

T. S. S. R. K. Rao (2000)

Extracta Mathematicae

For a compact Hausdorff space K and a Banach space X, let WC(K,X) denote the space of X-valued functions defined on K, that are continuous when X has the weak topology. In this note by a simple Banach space theoretic argument, we show that given f belonging to WC(K,X) there exists a net {fa} contained in C(K,X) (space of norm continuous functions) such that fa --> f pointwise w.r.t. the norm topology on X. Such a function f is said to be of Baire class 1.

Weakly precompact subsets of L₁(μ,X)

Ioana Ghenciu (2012)

Colloquium Mathematicae

Let (Ω,Σ,μ) be a probability space, X a Banach space, and L₁(μ,X) the Banach space of Bochner integrable functions f:Ω → X. Let W = f ∈ L₁(μ,X): for a.e. ω ∈ Ω, ||f(ω)|| ≤ 1. In this paper we characterize the weakly precompact subsets of L₁(μ,X). We prove that a bounded subset A of L₁(μ,X) is weakly precompact if and only if A is uniformly integrable and for any sequence (fₙ) in A, there exists a sequence (gₙ) with g c o f i : i n for each n such that for a.e. ω ∈ Ω, the sequence (gₙ(ω)) is weakly Cauchy in X....

Weighted estimates for commutators of linear operators

Josefina Alvarez, Richard Bagby, Douglas Kurtz, Carlos Pérez (1993)

Studia Mathematica

We study boundedness properties of commutators of general linear operators with real-valued BMO functions on weighted L p spaces. We then derive applications to particular important operators, such as Calderón-Zygmund type operators, pseudo-differential operators, multipliers, rough singular integrals and maximal type operators.

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